Radio frequency switches are basic building blocks for communication and control systems and are used for multiplexing of signals to achieve system reconfigureability and dynamic control. Radio frequency switches may be used in such applications as portable/mobile/satellite communication systems (e.g. cell-phones, PDAs, laptops, phased array antennas, sensors, transceivers etc.). As communication systems approach higher data rate (gigabytes per second) and multi-functional operation, stringent requirements have been set for radio frequency switches. Some of these requirements include low power consumption, high reliability, high switching speed, high isolation, low insertion losses, ease of integration/implementation, as well as affordability. In particular, for 3G (third generation) wireless phones and space-based applications, low power consumption is critical to ensure reliable, long lifetime operation on limited power supplies. MEMS or solid-state based switches which are currently used are incapable of meeting future demands due to associated disadvantages. For example, MEMS devices utilize complicated manufacturing processes and are expensive to manufacture. FIG. 8 is a table comparing electronic, physical and cost properties of MEMS, solid state, and nanoionic switches.
Known radio frequency devices employ electronic, mechanical, or a combination of electronic and mechanical (electromechanical) processes to induce a change in state (on/off). Radio frequency switching applications usually employ solid state switches or microelectromechanical systems (MEMS), both of which possess associated weaknesses. Solid state diodes can be produced cost-effectively to operate at low voltages (1-3V) and high speeds (ns), but suffer from higher insertion loss, high DC power consumption, low isolation, and the generation of third-order harmonics/intermodulation distortion (IMD). MEMS-based switches provide low insertion loss (about 0.2 dB), low DC power consumption (about pW), high isolation (>30 dB), and good IMD performance, but exhibit reliability problems (e.g., stiction, moving parts), slower switching speeds (ps), high actuation voltages (5-50V) which require complex circuitry, and relatively complicated processing steps. Furthermore, MEMS packaging presents additional problems which need to be addressed before widespread use is realizable.
Advances in the area of radio frequency switches will be beneficial in various industries. The present disclosure addresses embodiments that may be applicable to switches, such as radio switches.